Die-head



L. SPREITZER,

DIE HEAD.

APPLICATION FILED JULY 5,1919.

1,376,647,, Patented Apr. 26, 1921.

2 SHEETS-SHEET I- -L-. SPREITZ EH- -DIE HEAD. APPLICATION maolsuur s 1919 2 SHEETSaSHEETZ.

M WWW? Patemed Apr- 26, 192i.

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LARENGE SPEEITZER, 0F HAMMOND, INDI ANA, ASSIGNOR T0 EDWARD VALVE AND DIE-HEAD.

LS'Y ILWM.

Application filed July 5,

To all to ham it may concern:

Be it known that I, Lannnon Srnnrrznn, a citizen of the United States, residing at Hammond, in the county of Lake and State of Indiana have invented a certain new and useful Improvement in Die-Heads, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

My invention relates to die heads.

In cutting threads with a die, particularly where a short thread is to be cut on stock of a relatively large diameter it is necessary that the die be stopped accurately and promptly at the end of the thread particularly before the die strikes a shoulder or projection on the work.

I am aware that prior to my invention it has been proposed to provide an automatically releasable die which will be automatically opened to release the threaded stock by engagement of a tripping member with a stop secured to or on the ways or other stationary member of the lathe. This has not been satisfactory because it is necessary to have the stock extend from the chuck a uniform distance each time. It has also been proposed to place a stop between the jaws of the die, but many of the devices so far offered along these l;nes have not possessed.

all the characteristics desirable in such a device. I

My invention provides an improved form of automatically releasable die mechanism which opens the dies under the control of a trigger engaged by the outer end of the stock. Thus the opening of the die is directly controlled by the length of the stock which has been threaded.

My invention further provides improved means for closing the dies, for mounting the same, for adjustment of the dies and for controlling the holding and releasing of the dies. Numerous improvements in detail will. be apparent from the following detail description and the accompanying drawings which form a part of the same. The invention is not necessarily limited to the cutting of threads. as the invention may be applied to any analogous use. It is also to be understood that while I have illustrated my invention as applied to the usual form of lathe, the device may be applied to a turret lathe and may be automatically operated Specification of Letters Patent. Patented Apr. 26, 1921.

Serial No. 308,751.

both asto opening the jaws of the die and also closing of the same.

Briefly I provide a main body member which bears guides for the jaws the jaws being movable toward each other by suitable cam means which may be manually or automatically controlled. The frame also bears detent members which engage in notches or shoulders in thejaws or parts connected to the jaws. An axial or central trigger member is connected to the detent so that when the end of the stock in passing through the dies engages the central trigger member it releasesthe detents from the shoulders permitting springs to move the jaws outwardly. In order to acquaint those skilled inthe art with the manner of constructing and practising my invention I shall now describe in connection with the accompanying drawings one embodiment of the invention.

Figure 1 is a side elevation of a die head embodying my invention; 7

Fig. 2 is a longitudinal vertical section of the same;

Fig. 3 is a horizontal longitudinal section;

Fig. 4 is a front elevational view;

Fig. 5 is a fragmentary view illustrating the cam or crank mechanism for closing the jaws of the die;

Fig. 6 is a fragmentary general view illustrating the manner of use of the device; and

Fig. 7 is a perspective view of the forward v end of the detentmember.

The die head which is shown in the drawings consists of a main frame or body mem-v ber 1, which in this case is formed in the shape of a rather short thick-walled cylindeer with a flange or head portion 2 formed integral therewith. A tail piece orstem a is loosely mounted in the rear end of the cylinder closing the bore 3. The fit of this a tail piece or stem within the bore of the cylinder is made purposely rather loose so that sufficient play will be permitted to admit ofthe jaws alining themselves with the stock which is to be threaded. Set screws 5 are threaded into the walls of the cylinder 1 and engage in suitable sockets in the enlarged portion 6 of the tail piece or stem i to prevent turning of the tail piece with respect to the cylinder or frame 1. The inner ends of the screws .5 are reduced and these reduced ends it rather loosely in the holes or sockets provided for them so that the play above described may occur.

The head of flange 2 is machined and formed to provide guiding surfaces or ways for the slide members 7 and 8 which bear the cotiperating die members 9 and 10 respectively. Cover plates 12 and 13 are fastened above and below the slide members 7 and 8 to engage the shoulders 14 and 15 which are formed on the slide members 7 and 8. In this manner a suitable guide is formed.

The jaws 9 and 10 have cutting faces 17 and 18 respectively, in this case adapted to cut screw threads. The jaws 9 and 10 are mounted upon the slides 7 and 8 in any suitable manner, in this case by means of the set screws 19 and 20, which are mounted in brackets 21 and 22 and the clamping screws 23'and 2 1- which lie in suitable slots in the die members. The set screws 19 and 20 are provided to adjust the die members in and out. These set screwsare mounted in the brackets 21 and 22 which are secured upon the ends of the slides 7 and 8. The clamping screws .23 and 24 are threaded into suitable holes in the slide members 7 and 8 and serve to clamp the jaws in adjusted position. In this manner the jaws are securely fastened to the slide members. The slide members, however are movable in the guides toward and away from the axis of the frame member 1.

The slide membersare cut away to form a passageway or opening 25 of substantially the same size as the bore 3 in the frame or body 1.' Compression springs 26 are set in suitable sockets in the slide members 7 and 8 and tend at all times to push the slide members away from each other. The slide members 7 andv 8 are provided with recesses 27 and 28 which provide shoulders adapted to beengaged by the ends of the rods 29 and 30. These rods which serve as detents have their inner ends provided with flat faces for engaging the shoulders so that a fairly large area of contact for supporting the outward thrust of the die'members is provided. The extent to which the detents 29'and 30 enter the recesses 27 is limited by'shoulders 32 which determine the extent of the flat faces 31 as shown in Fig. 7

At their rear ends the two rods 29 and 30 are connected together by a cross bar 33, these rods or detents being pinned or otherwise secured to the cross bar. The rear end of the frame or body 1 is recessed to permit the cross bar to slide back and forth as will be described later. The rods 29 and 30 are reduced in diameter at their rear ends where they pass through the cross bar 33 and the extreme rear ends of these rods are guided in suitable collars 35 and 36 which. collars are threaded into suitable sockets in the rear end face of the body member 1. Compression springs 37 and 38 lie between the adj acent faces of the cross bar 33 and the collars 35 and 36 tending always to thrust the de tents 29 and 30 together with the cross bar 33 toward the front of the device so that the ends of the detent may drop into the recesses 27. and 28 in the slide members 7 to 8.

The disengagement of the detent members 29 and 30 from the recesses in the slide members 7 and 8 is controlled by the trigger member 40 which in this case is formed of a thin plate of steel with its front edge pre sented toward the forward end of the device. The trigger or contact member 10 is of a length just sufficient to clear the internal diameter of the cylinder or frame member 1 with a little clearance. This finger or trigger member 40 is mounted in the end of a rod 41-1, the end of which is notched to receive the same, and which rod is guided through the hub 42 of the cross arm member 33. The rod 11 is adapted to be clamped to the cross arm member 33 so that engagement of the stock with the finger or contact plate 40 will force the cross arm 33 and the detents 29 and 30 toward the rear to release the slide members 7 and 3 with their coiiperating dies to disengage the stock after the same has proceeded the proper distance inwardly. The finger member 40 and rod'tl are preferab y mounted so as to prevent the turning of the same and in this case I have cut a groove or key-way 4-3 in the upper surface of the rod 411 and have provided a clamping member M which consists of a rod threaded at its lower end into a suitable opening 15 and a suitable handle or wheel 43 at the upper end. The I innermost end of the stem 4L4 is reduced in diameter to correspond to the width of the slot or keyway 43, this reduced extension 47 being adapted to lie at all times in said slot and to prevent turning of the rod a1 and contact member 20. A spring4e8 is placed between the hub 12 of the cross arm 33 and the contact member 40, but this normally serves no function. This spring is employed to push the contact finger and the connected ro: 41-1 forward when the clamping member all s released so that the adjustment of the trigger may be readily made.

,The slide members 7 and 8 inwardly by hand to engage the detents 29' anc 30, but I have shown crank operated means for performing this function. "A bracket 50 is mounted on the upper surface of the body or frame member 1 near the front end of the same and a short crank shaft 51 is journaled in the same. The rear end of the shaft 51 is connected to a handle- 52 for turning the shaft. At its other end this shaft 51 is provided 53 having a crank pin 5%. The crank pin has a link or rod 55 provided with suitable shoulders 56 and shown in Figs. 1 and 5 for engaging the fingers 58 and 59 of the bell crank levers 60 and 61. Thebell crank levers 60 and 61 are mounted on pins 62 and 63 which are set may be pushed 57 at its lower end as vith a crank disk in the upper corners of the flange member 2. The flange member 2 is slotted out to receive the bell crank levers 60 and 61. At their lower ends the bell crank levers 60 and 61 are connected to the slide members 8 and 7 respectively by the pins 66 and 65 which are threaded into the slide members. The levers are suitably slotted to receive the pins 65 and 66 and the flange member 2 is also slotted to permit movement of the pins in their in and out motion. The link 55 is guided by a pin 70 which is formed as the rearward extension of one of the screws 71 which fastens the cover plate 12 in position. This pin 70 passes through a slot 7 2 formed in the link. It will be noted that the shoulders 56 and 57 on the lower end of the link 55 are of different lengths because of the eccentric position of said link. The handle 52 has been shown in the raised position in the drawings but this handle normally lies down against the body 1 by its own weight.

The operation of the device is as follows: The stem l is gripped by a suitable socket or chuck which may in turn be mounted on the feed carriage or on the tail stock of alathe, as shown at 75 in Fig. 6. It is necessary to provide means for forcing the dies to take hold and the dies will then automatically feed forward. To this end provision should be made to let the device feed itself after the threads are started. The body 1 may be supported solely on the stem 4 or it may be mounted on a rest 76 as shown in Fig. 6. The stock or member to be threaded, as shown at 77, is gripped in a suitable chuck 78 so that it may be rotated for forming the threads.

The die jaws are previously set for the proper diameter of stock to be threaded and the trigger member 40 is set to release the detents 29 and 30 when the stock has advanced a suitable distance in the dies.

The setting of this trigger mechanism is accomplished as follows. The detents 29 and 30 are released either by pushing back on the contact finger 4:0 or on the handle 46 of the clamping screw 44;. The slide members 7 and 8 spring outwardly and hold the detent members 29 and 30 in their rear position. released by turning the wheel 46 until the reduced stem 47 disengages the bottom of the groove 43. The rod 41 and contact member 40 then move forward under the influence of the spring 48 to the desired position, which may be measured by a scale or ruler inserted betweenthe jaws 9 and 10. If the stock is to be threaded for a half inch, the front face of the contact finger 4:0 is set a half inch back of the front edge of the jaws 9 and 10. The handle 52 is then raised to bring the slide members 7 and 8 to their inner positions so that the detents 29 and 30 dropinto the recesses 27 and 28, holding the The clamping screw 44 is then die members 9 and 10 in proper position for threading the stock. It will be noted that the trigger or contact member 10 will move forward a slight distance due to the detents 29 and 30 dropping into their sockets. Howeve-r, the release of the slides 7 and 8 and of the die members 9 and 10 will occur when the end of the stock has pushed the trigger or contact member 10 back the corresponding distance. The degree to which the stock is to be threaded may thus be suitably con trolled. When the jaw members 9 and 10 spring outwardly they release the stock and there is no further tendency for them to feed the same.

The body or frame member is made relatively long so that a fairly long thread may be out. As shown in Fig. 2, the contact or trigger member 40 is set for a relatively long thread. The advantages to be gained by this construction are obvious. The jaw members are held rigidly in place and they release instantly, giving a highly satisfactory operation.

It will be understood that the device is capable of modification in form, dimensions and proportions and that the device may be used for other purposes. I do not intend to be limited to the precise construction shown and described.

I claim:

1. In combination, a body member having an axial bore and having guides arranged transverse to the bore, slide members mounted in said guides, means tending to force said slide members laterally, cutting jaws secured to said slide members, detent members for the slide members, said detent members being suitably guided on said body member, said slides having shoulders adapted to be engaged by said detent members, a contact member forming a trigger, said contact member being mounted substantially axially of said bore, and being connected to said detent members and spring means tending to hold the detent members in engagejgnent with the shoulders of the slide memers.

2. In combination, a body member having guides, a pair of slides in said guides, spring means tending to force the slides apart, detent means for holding said slides in inward position, said detent means comprlsmg a pair of rods adapted to be moved axially, a cross bar connecting said rods, spring means for holding the rods in engagement with the slides, a trigger member having its forward end adapted to engage the stock entering the cutting aws and being'guided in said crossbar, and meansfor adjusting the setting of said trigger member in said crossbar. 1

3. In combination, a pair of slides, a pair of detents comprising rods axially movable, a cross bar connecting said rods, said cross bar having a rod passing through the central portion of the same, said rod having at its forward end means for engaging the stock and screw threaded adjusting means for adjusting the setting of said engaging means, and for preventing the rod from turning in the cross bar.

4. In combination, a body member, a pair of slides guided on said body member, said slides having cutting jaws, spring means tending to force said slides apart, detent means for holding said aws in inward position, trigger means for disengaging the detent means from the slides, said trigger means being adjustable to control the length of stock operated upon, crank means for moving the slides inwardly and a handle for manipulating said crank means.

In combination, a slide member bearing a cutting device, a body member in which said slide member is guided, said slide having a recess forming a shoulder, a detent adapted to enter said recess and carrying a bar, a trigger member connected to said detent, said trigger member comprising a plate set edgewise with respect to the stock fed into the cutting member, and a rod adjustably connecting said plate and said bar.

6. In combination, a slide member bearing a cutting device, a body member in which said slide member is guided, said slide having a recess forming a shoulder, a

detent adapted to enter said recess, an extension on said detent, a trigger member connected to said detent, said trigger mem ber comprising a plate set edgewise with respect to the stock fed into the cutting device,a rod connecting said plate and said detent extension, and screw threaded adjusting means for adjusting the position of said latter rod to said detent member.

7. In combination, a cylindrical body member having an axial bore, said body member having a flanged head at the frontend thereof forming guides, said body member having a stem loosely secured in said hollow bore, slides mounted in the guides on said flanged head, cutting aws mounted on said slides, said slides having recesses forming shoulders, spring means for forcing said slides apart, rods guided in the walls of said body member, said rods being adapted to enter the recesses and to engage said shoulders, said rods forming detent means, a crossbar connected to each of said rods and a trigger member comprising an outer contact member and a connecting rod, said connecting rod extending through said cross bar and being adjustable in said cross bar.

8. In combination, a cylindrical body member having an axial bore, said body member having a flanged head at the front end thereof forming guides, said body member having a stem loosely secured in said hollow bore, slides mounted in the guides on said flanged head, cutting jaws mounted on said slides, said slides having recesses forming shoulders, spring means for forcing said slides apart, rods guided in the walls of said body member, said rods being adapted to enter the recesses and to engage said shoulders, said rods forming detent means, a cross bar connected to each of said rods, and a trigger member comprising an outer contact member and a connecting rod, said connecting rod extending through said cross bar and being adjust able in said cross bar, a pair of levers connected to said slides and manual means for operating said levers to force the slides in ward against said springs.

9. In combination, a body or frame mem ber providing guides, slides mounted in said guides, spring means tending to force said guides apart, detent means for holding the slides in their innermost position, automatic trigger means for releasing said detents, a pair of levers each connected to one of said slides and common cam means for operating both of said levers to move the slides inwardly against said springs.

10. In combination, a pair of slides, means for forcing said slides outwardly, detent means for holding the slides in inwarc position, a pair of hell crank levers connected to said slides at one end of each of said levers respectively, manually operable crank means and a link connecting said crank means with the opposite ends of said bell crank levers for moving said slides toward each other.

11. In combination, a movable cutting jaw, a spring for moving the jaw away from the stock, a guide for guiding the jaw laterally, a frame or body member support ing the guide, spring pressed detent means mounted on the frame or body member to hold the aw against the stock, trigger means engageable by the stock for releasing the detent means against spring tension, a lever engaging said jaw, and means for actuating the lever to move the jaw inwardly into an engaging position.

12. In combination, a body or frame member having a pair of slides, said slides being adapted to carry cutting members, said slides having recesses forming shoulders, rods adapted to engage in said recesses against said shoulders, a crossbar connecting said rods, spring means tending to force said rods into said recesses, and a trigger member comprising a' forwardly extending contact member and a connecting rod for connecting said contact member with said crossbar, and means for adjusting the connection having recesses forming shoulders, rods adapted to engage in said recesses against said shoulders, a cross-bar connecting said rods, spring means tending to force said rods into said recesses, a trigger member comprising a forwardly extending contact member and a connecting rod for connecting said contact member with said crossbar, a spring for moving said rod in said bar, and means for locking the rod in an adjusted position.

let. In combination, a body member having guides, a pair of slides in said guides, cutting jaws on said slides, spring means tending to force the slides apart, means comprising a pair of rods adapted to be moved axially, a cross-bar connecting said rods, spring means for holding the rods in engagement with the slides, a trigger member having its forward end adapted to engage the stock entering the cutting jaws and being adjustably fixed in the cross-bar, and means tending to move said trigger member between said jaws.

In witness whereof I hereunto subscribe my name this 25th day of June, 1919.

LARENCE SPREITZER. 

